Apparatus for coating wire with varnish and the like



Feb. 26 1924. 1,485,254

WQA. 01cm:

APPARATUS FOR COAI'IQIC! WIRE WITH VARNISH AND II-II LIKE "10d Jan. 10 1922 2 Shoots-Sheet 1 m INVENTOR WILLIAM A DICKIE 3 BY HIS AT'ICRNEY;

Feb. 26 1924. 1,485,254

w. A. DICKII:

APPARATUS roa comm: nu ma wumxsn MD m was l'llod m. 10. x92: 2 Shunt-She a VIILLIAI A. x'ncn'a a a; HIS runwa s;

l have invente coating material passes up axia '1 and it may be heated; Means may be new Feb. 26.1924.

um'rsn s raras i 1,485,254 Par-am ormer.

mun! ALEXANDER DIOKII, OF SPONDON, NEAR nmv, ENGLAND, 881G808 1'0 AIEBICAN OELLULOBI OHEIICLL ILNUI'LOTURIHG comm A I CORPORATION 01' DELAWARE.

LPPLBA'I'US I'OB COATING wm WI'.I.H VAR!!! m m an.

Application fled January 10, 198i. leriallo. 588,816.

To all whom it may concern: Be it known that I Wnmau Amxnmm Drcxm, a subject of the King of Great Britain, of S ondon, near Derby, En land,

d certain new and usefu Improvements in Apparatus for Coating Wire with Varnish an the like, of which .the following is a specification. This invention consists of improvements in in ap aratus for coating wire with dope,

varms or similar preparations, more especially for electric insulating urposes, and relates to apparatus of the kind in which the wire, after assin through a bath or su ply 16 of the liqui coating preparation, trave on through a device for removing surplus coatinfi preparation therefrom. g

- e invention is particularly intended for coating bare wire with viscous insulatac ing dopes or varnishes of cellulose acetate or ot er cellulose derivatives dissolved in'volatile solvents without or with plastifiers or other additions. For such purposes it is very important that the coatm ap lied to 26 the wire shall be very even an uni orm This result is attained byth'e resent invention by means of a rotary tubu ar doctor through which the wire carryin the liquid and cantrally, the surplus removing or' cc of the rotary tubular doctor, surrounding and becoaxial with the wire travelling thro ugh In combination with the; said rota tubular doctor disposed coaxially with t e line of travel of the wire and having its surplus removin orifice surrounding and coaxial therewit ,I may employ immediately above a it a tube, passage, or chamber hereinafter referred to as an evaporation controlling chamber which is ada ted to .enable the dope or preparation carri by the travelling wire to evaporate in an atmosfhere containing volatile solvent liberated mm the dope or preparation on the wire, and thereby prevents too rapid. evaporation and irregular setting of the coating on the wire. The said tube or passage may beunheated, or if de- P vided for priming the eva oration-controllingtube, passage or cham r with solvent jvapour at commencement of working pr fer-.lreepingit replenished with solvent va- -rately centere pour during working. Such means may for example consist of needle-valve controlled container discharging into the tube, passage or chamber; or an annular or other trou b may be provided at the bottom of the tu passage or chamber and be filled with liqu1d volatile solvent, or both such means may be provided. The wire may if required pass on from the evaporation tube, passage or chamber through a heated tube or chamber, in order to drive all any remaining volatile solvent and dry off the coating. The accompanying drawings illustrate by way of example two forms of wire coating apparatus constructed in accordance with the invention. 7

Fig. 1 is a sectional side elevation of the coating and evaporation devices according above the container, the upper orifice of this doctor being restricted so as to remove surplus dope .and leave a suflicient uantity on the wire for the required tickness of coating The doctor tube is accuso that the wire p cantrally up through it, and it is provided with a cord pulley 6 for rotating it at a suitable speed (c. g. about 1500-2000-R. P. M.) about its axis Wlth a view to neutralizing any ecocntricities in the orifice and for facilitating equal distribution ofthe dope aroundthe travelling wire by the restricted orifioe of the doctor; It is possible that the viscous dope or coatingpreparation may creep or flow slowly down the travelling wire after.

this has assed up through the doctor, but' it is-foun that by rotating the doctor as te ferred to, a sufliciently even ooating may be obtained on the wire. Also the return of the surplus dope removed from the wire tothe container may be facilitated by the rotation of the doctor tending to, throw it back into the-container. Above the doctor 5 is mounted a vertical tube made in. two 800- loo tions 7 7, preferably divided by a partiany convenient means.

the tube 7 by an u or be otherwise grou oration and too rapid vm g chambers 'ber16.whichislieated steam-.i c'ontrolledbyvalves18.

tion 8 with a central orifice 8 for thmpassage of the wire, and the top end of the portion 7 is also preferably closed except for a central opening 9 for the n of the wire. The upper tube or cham r 7 is heated by a steam coil 12 or otherwise for the purpose of d out remaining solvent as the wire trave on. After leaving the tube 7 the wire p on over a pulley 13 and is finally wound on a wind-up reel 14. The reels 2 and 14 may be driven by will be seen that the coat on the wire travelling up through the tube can evaporate in an atmosphere containing vapour or solvent liberated therefrom too rapid evapshrinlrage of the coating on the wire be' thus prevented.

represents-a sma container for liquid solvent (e. g.- acetone) which ma provided for priming the tube 7 '1 vapour at the commencement or for keeping the tube re lenished with volatile solvent during wor this container discharging into the upperpart of the tube 7 and its de ivery being controlled by a needle valve 10.- An annular trough 11, formed in the bottom of pstan annular lip 11 surrounding the nozzle of t e doctor, is also shown as provided for the priming or replenishing of the tube with va ur, 11" bemg an overflow from the troug' An number of doctors and tubes such as described my of course be a pod, to with any desired number of wires, which ma be led through a common coating bath an thence up through the doctors and tubes.

Referring now to Figs. 8 and 4, these illustrate another form of apparatus. in

whicha single.;evaporation-controlling and drying at common-to a number 9! tdloctnttubes is empllooyed t1:801"! dealwi e wires issuing m octor m 15 indicates the coat bath dism ss: c we y co p wires from'wind-o reels 2, over guide pu l l eys 3 onthebath,roundguidep dinthe bath and thence u through doctor tubes 5 PI'QVIOUS. nk-l :lhe evaporation-controlling and final dry-v in this construction are constltuted a casing of flat, box-like form, divided mto a lower section 16 and n upper section 16 by atpeartition 20 f0 1 with slots or holes for t slots or holes beingolikewise pro; vided in the closed .top of upper as am hes i1 lee i r tu up o in the bottom of chamber 16 common to the wires, tr'a bet and t e final-dryingtu lin the number and group' ration-controlling efie'ct even with an open this chamber and the upper m thro h heatg chamber 16", thence over the guide may be provided for conveying away and recove the solvent :vapours from the tubes 7- or chambers 16-46.

It is of course to be understood that the particular a paratus described and illustrated are given only b3 we of example and may bevaried consi erab y without eparting from .the invention. The-ova ration controllin tube or chamor chamber may be made se arate and distinct from eac other. Or t ey may 0 n freely into each other or form one tu or chamber with its upper portion heateds Or the final drying tn or chamber may be dispensed with, the evaporation-controlli tube or chamber be' heated or not. 'e evaporation-contro u tube or chamber and the final drying tu or chamber when employed, may of course be of any suitable cross section and dimensions acco to of the doctor devices which they serve. though it isimuch better to enclose the evaporation-contro chamber or combinedevaporation-con ling and final heating chamber for more eficiently attaining the result of enabling thecoatmgtoeva rateintheatmo of solvent hbera therefrom, and or recoveringfhe solvent vapours, it has been found t it is pomible to attain the evapotube or chamber by eve ration-controlling l d ent y ong an small or this sufici narrowinsection.

What I claima'nd desire LeItteIrIsIPatent"is:f m a ratus or coating wire viscous dope or varnish ctnitairv ing VOMiIQQlYBllL-ihfl combination with means .forsupplying'the liquid coating to a tra wiretizf arotaryitullmlardoctor 0:100. m I, the lin efiiilz i-avel'of the w1re,an its or -i -".nd2?;i.1ami I means for rapidly dogoiaboutitsagrs. 4 I pp v-- vi ingvolatilesolvent,c0m risingin: ticn a liquid coating tosecureby combinadoctor dis above said bath co-axially with the line of travel of the wire and having its surplus removing orifice surrounding and co-ax1al therewith, means for causing the wire to travel through said bath and u through said rotary tubular doctor, an

means for rapidly rotating said tubular doctor about its axis.

3. Apparatus for coating wire with viscous insulating dope or varnish containing volatile solvent, comprising in combination a liquid coating bath, a rotary tubular doctor disposed above said bath coaxially with the line of travel of the wire and having its surplus removin orifice surrounding and co-axial therewith, an evaporation controlling chamber disposed above said rotary tubular doctor, means for causing the wire to travel through said bath and up through said rotary doctor and eva oration controlling chamber, and means or rapidly rotating said tubular doctor about its axis.

4. Ap aratus for coating wire with viscous insulating dope or varnish containing volatile solvent, comprising in combination a liquid coating bath, a rotary tubular doctor disposed above said bath coaxially with the line of travel of the wire and having, its surplus removin orifice surrounding and co-axial therewith, an evaporation controlling chamber disposed above said rotary tubular doctor, means for causing the wire to travel through said bath and up through said rotary doctor and evaporation controlling chamber, means for supplying liquid volatile solvent to said evaporation controlling chamber, and means for rapidly rotating said tubular doctor about its axis.

5. Apparatus for coating wire with viscous insulating dope or varnish containing volatile solvent, comprising in combination, a liquid coating bath, a rotary tubular doctor disposed above said bath coaxially with the line of travel of the wire and having its surplus removin orifice surrounding and co-axial therewit an evaporation controllin chamber disposed above said rotary tubu ar doctor, and a heated final drying chamber located above said evaporation controlling chamber, means for causing the wire to travel through said bath,

rotary tubular doctor, evaporation controlling chamber and final drying chamber, and means for rapidly rotating said tubular doctor about its axis.

In testimony whereof I have hereunto subscribed my name.

WILLIAM ALEXANDER DICKIE. Witnesses:

Tnos. H. Coon, E. W.- KNIGHT. 

